A 4th comment in the line with the rest because of the reddit 10.000 character limit :

Harpoon gun - very slow reload , only works at close range , high damage and could stick a zombie to the wall or instakill it - it deals normal damage to the bosses , insignificant enough vs bosses because of the long reload speed.

https://sketchfab.com/3d-models/harpoon-rifle-5456adeff51947d5bf66a4563bb3821f

https://sketchfab.com/3d-models/harpoon-gun-dcc0bb44b6ff4661ac79061d468a4b3f

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Stake Gun - its a gun that launches stakes , they are heavy and do significant damage to small targets , 1 shot per reload with a longer reload but higher damage (to balance the high reload time)

https://sketchfab.com/3d-models/stakes-gun-19b761069685408fa60158447610d958

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Throwing Weapons - as a playstyle , not necessarely as stealth weapons. Just fun stuff to throw at zombies :

https://sketchfab.com/3d-models/dart-05cf831e62cb4107bc42609d1de6d69e

https://sketchfab.com/3d-models/ninja-razor-tactical-throwing-knife-1e1ce0c12205403c9600832c4c8649c6

https://sketchfab.com/3d-models/shuriken-05cddb5bd4cb47c7843afdbb985d212a

https://sketchfab.com/3d-models/blade-boomerang-0b09ea1c97c1484d98863b5d92f49bb7

https://sketchfab.com/3d-models/m48-hawk-tactical-tomahawk-pbr-game-ready-264bef22a84149eca2e95f3c31edb750

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Nail Gun - plain and simple , it shoots nails , should be counted simillary to a smg but dosent do a lot of damage , it only works on short range (probably best suited for t1 or start of the game)

there are so cool models here that i didnt know where to choose from!

https://sketchfab.com/search?q=nail+gun&type=models

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